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Interannual variations of the Somali Jet in the Arabian Sea during 1988-99 were linked to El Nino and La Nina episodes and to India west coast rainfall.
The level 2 aerosol backscatter and extinction profiles from the NASA Micropulse Lidar Network (MPLNET) at Kanpur, India, have been studied from May 2009 to September 2010. Monthly averaged extinction profiles from MPLNET shows high extinction values near the surface during October March. Higher extinction values at altitudes of 24 km are observed from April to June, a period marked by frequent dust episodes. Version 3 level 2 Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) aerosol profile products have been compared with corresponding data from MPLNET over Kanpur for the above-mentioned period. Out of the available backscatter profiles, the16 profiles used in this study have time differences less than 3 h and distances less than 130 km. Among these profiles, four cases show good comparison above 400 m with R2 greater than 0.7. Comparison with AERONET data shows that the aerosol type is properly identified by the CALIOP algorithm. Cloud contamination is a possible source of error in the remaining cases of poor comparison. Another source of error is the improper backscatter-to-extinction ratio, which further affects the accuracy of extinction coefficient retrieval.
The Northwest India Aquifer (NWIA) has been shown to have the highest groundwater depletion (GWD) rate globally, threatening crop production and sustainability of groundwater resources. Gravity Recovery and Climate Experiment (GRACE) satellites have been emerging as a powerful tool to evaluate GWD with ancillary data. Accurate GWD estimation is, however, challenging because of uncertainties in GRACE data processing. We evaluated GWD rates over the NWIA using a variety of approaches, including newly developed constrained forward modeling resulting in a GWD rate of 3.1 plus or minus 0.1 centimeters per acre (or 14 plus or minus 0.4 cubic kilometers per acre) for Jan 2005-Dec 2010, consistent with the GWD rate (2.8 centimeters per acre or 12.3 cubic kilometers per acre) from groundwater-level monitoring data. Published studies (e.g., 4 plus or minus 1 centimeter per acre or 18 plus or minus 4.4 cubic kilometers per acre) may overestimate GWD over this region. This study highlights uncertainties in GWD estimates and the importance of incorporating a priori information to refine spatial patterns of GRACE signals that could be more useful in groundwater resource management and need to be paid more attention in future studies.
Assessment of actual evapotranspiration (ET) is essential as it controls the exchange of water and heat energy between the atmosphere and land surface. ET also influences the available water resources and assists in the crop water assessment in agricultural areas. This study involves the assessment of spatial distribution of seasonal and annual ET using Surface Energy Balance Algorithm for Land (SEBAL) and provides an estimation of future changes in ET due to land use and climate change for a portion of the Narmada river basin in Central India. Climate change effects on future ET are assessed using the ACCESS1-0 model of CMIP5. A Markov Chain model estimated future land use based on the probability of changes in the past. The ET analysis is carried out for the years 2009-2011. The results indicate variation in the seasonal ET with the changed land use. High ET is observed over forest areas and crop lands, but ET decreases over crop lands after harvest. The overall annual ET is high over water bodies and forest areas. ET is high in the premonsoon season over the water bodies and decreases in the winter. Future ET in the 2020s, 2030s, 2040s, and 2050s is shown with respect to land use and climate changes that project a gradual decrease due to the constant removal of the forest areas. The lowest ET is projected in 2050. Individual impact of land use change projects decreases in ET from 1990 to 2050, while climate change effect projects increases in ET in the future due to rises in temperature. However, the combined impacts of land use and climate changes indicate a decrease in ET in the future.
The accurate estimation of soil moisture (SM) using microwave remote sensing depends mostly on careful selection of retrieval parameters among which the soil dielectric mixing model is the important one. These models are often categorized into empirical, semi-empirical or volumetric based on their methodologies and input data requirements. To study in detail, the comparative performance of four dielectric mixing models -- Wang & Schmugge model, Hallikainen model, Dobson model and Mironov model were used with Soil Moisture Active Passive (SMAP) L-band brightness temperature and Single Channel Algorithm for SM retrieval over agricultural landscapes in India. The highest performance statistics combination in terms of Root Mean Square Error (RMSE), correlation coefficient (R^(2)) and percentage bias (PBIAS) against the concurrent in-situ SM measurements were calculated at the selected validation sites. The overall results indicate that the best performance was given by the Mironov model (RMSE = 0.07 cu. m/cu. m), followed by Wang & Schmugge model (RMSE = 0.08 cu. m3/cu. m), Hallikainen model (RMSE = 0.09 cu. m/cu. m), Dobson model (RMSE = 0.10 cu. m/cu. m) and original SMAP radiometer SM (RMSE = 0.12 cu. m/cu. m). Findings of this study provides important insights into application and performance of dielectric mixing models in mapping surface SM variations. This study also underlines the pivotal role of local conditions for SM retrieval which should be carefully included in the algorithms.
Uncoordinated management of hydropower dams during extreme and unexpected precipitation events in mountainous terrain can have disastrous consequences due to the competing nature of flood control and hydropower generation. Numerous cases of flooding events that have been exacerbated due to insufficient storage conditions in hydropower dams have been reported worldwide. There is a need for a scalable and publicly accessible monitoring framework that is capable of providing reliable, near-real time, and transparent reservoir operations data. A fully satellite-based framework is the most viable solution to build such capability. The Reservoir Assessment Tool (RAT 3.0), which utilizes high frequency remote sensing-based surface area and reservoir storage estimation alongside hydrological modelled inflow was applied here for the 2018 Kerala floods in India as a globally representative case for a mountainous river basin with high precipitation and hydropower dams. Application of satellite-based RAT 3.0 in monitoring the state of 19 reservoirs in Kerala during the flood event showed very promising results. In general, RAT 3.0, using satellite remote sensing, was found to be able to capture the temporal trend of the reservoir storage and pinpoint the sudden shift in filling or release decisions made by the dam operator. Inflow modelling in such regions was found to require careful calibration with identification of reservoirs that are heavily regulated being a critical aspect. The perennial high cloud cover in such regions necessitate and highlights the central role played by microwave and radar-based satellite sensors, such as the Surface Water and Ocean Topography (SWOT) mission, in tracking reservoir state. An operational version of RAT 3.0 for stakeholder agencies tailored for hydropower dams operating in high precipitation and mountainous environments is a real-world outcome of this study.
Cumulative precipitation in northern India in June 2013 was a century-scale event, and evidence for increased probability in the present climate compared to the preindustrial climate is equivocal.
This fact sheet provides an annual update on 21st Century Power Partnership activities in our partner country, India.
The time when energy-related carbon emissions come overwhelmingly from developed countries is coming to a close. China will soon overtake the United States as the world’s leading emitter of greenhouse gas emissions. Meanwhile, India also seems to be on track to experience rapid long-term economic expansion. With this growth will surely come continued massive growth in energy demand. This paper explores the dynamics of that demand growth for one sector – residential electricity – and the realistic potential for coping with it through efficiency.
The National Solar Radiation Database (NSRDB) provides high-resolution solar radiation data for long periods of time, which allows user to have a clear understanding of the spatial and temporal correlation of the data to determine the true impact of solar variability on the grid. This fact sheet specifically outlines solar resource data for India included in NSRDB.
Objective: To determine the efficacy and safety ultrasound-guided percutaneous catheter drainage (US-PCD) in management of various types of ruptured amebic liver abscess including free rupture (FR) with diffuse intraperitoneal fluid collections (DIFC). Methods: This study analyzed 117 patients with ruptured ALA who underwent US-PCD. The indication for US-PCD was failure to respond to conservative treatment and/or percutaneous needle aspiration. Results: Majority of patients were locally fermented alcohol abusers (95%), and malnourished (75%). Ninety-eight patients had intraperitoneal rupture including 66 contained rupture (CR) with localized intraperitoneal fluid collection (LIFC) and 32 FR with DIFC. Pleuropulmonary complication was found in 19 patients including 13 pleural and 6 pulmonary. A total of 333 catheters were used to drain 202 abscess cavities and associated fluid collections. US-PCD was technically and clinically successful in all cases. Multiple sessions (median 2; range 2–5) of PCD required with upsizing the catheter (median 14 F; range 14–20 F) and placement of additional catheter in 26 (22%) patients. The patients with FR with DIFC required more number of catheters (p = 0.01) and had longer hospital stay (p = 0.01). No major procedure related complication was observed. Six patients developed secondary bacterial infection; two of them presented with cavito-cutaneous fistula at catheter insertion site, and one with cholangitis due to biliary stricture formation necessitating subsequent endoscopic treatment. Post-procedural death occurred from sepsis in a patient with FR. Conclusion: US-PCD is a safe and effective mode of treatment for ruptured ALA including FR with DIFCs. We recommend PCD as a first-line therapy for ruptured ALA.
The Paleoproterozoic phosphorites constitute an economically significant component of the Sonrai basin of Lalitpur district. These are associated with ferruginous shale, ironstone, limestone and quartz breccia. Petro-mineralogical studies of samples of the phosphorites, using X-ray diffractometry and scanning electron microscopy, reveal that the collophane (carbonate-fluorapatite) is the dominant phosphate mineral. Calcite, dolomite, quartz, mica and haematite are the dominant gangue constituents. The phosphate minerals occur as oolites mutually replaced by carbonate and silica. The presence of iron oxides has been found in most of the thin sections. There is meagre evidence of organic matter in the form of filaments of microbial phosphate laminae in the samples of phosphorite. The mineral assemblages, their texture and various forms in these phosphorites may be due to some environmental vicissitudes followed by replacement processes and biogenic activities.
The mountain rivers of the Indian Himalaya possess a vast potential for hydropower generation. After decades of comparatively modest development recent years have seen a major intensification in the construction of new hydropower dams. Although increasingly portrayed as a form of renewable energy generation, hydropower development may lead to extensive alterations of fluvial systems and conflicts with resource use patterns of local communities. To appraise and reduce adverse effects is the purpose of statutory Environmental Impact Assessments (EIA) and corresponding mitigation plans. However, in the light of ambitious policies for hydropower expansion conventional approaches of environmental assessment are increasingly challenged to keep up with the intensity and pace of development. This paper aims to explore the systemic limitations of environmental assessment for hydropower development in the Indian state of Himachal Pradesh. Based on a qualitative methodology involving interviews with environmental experts, document reviews and field observations the study suggests that the current practice of constraining EIAs to the project level fails to address the larger effects of extensive hydropower development. Furthermore, it is critically discussed as to what extent the concept of Strategic Environmental Assessment (SEA) might have the potential to overcome existing shortcomings.
The environmental impact assessment of a process over its entire operational lifespan is an important issue. Estimation of life cycle emission helps in predicting the contribution of a given process to abate (or to pollute) the environmental emission scenario. Considering diminishing and time-dependent effect of emission, assessment of the overall effect of emissions is very complex. The paper presents a generalized methodology for arriving at a single emission discounting number for a process option, using the concept of time value of carbon emission flow. This number incorporates the effect of the emission resulting from the process over the entire operational lifespan. The advantage of this method is its quantitative aspect as well as its flexible nature. It can be applied to any process. The method is demonstrated with the help of an Intermediate Pyrolysis process when used to generate off-grid electricity and opting biochar route for disposing straw residue. The scenarios of very high net emission to very high net carbon sequestration is generated using process by careful selection of process parameters for different scenarios. For these different scenarios, the process discounting rate was determined and its outcome is discussed. The paper also proposes a process specific eco-label that mentions the discounting rates. - Highlight: • Methodology to obtain emission discounting rate for a process is proposed. • The method includes all components of life cycle emission converts into a time dependent discounting number. • A case study of Intermediate Pyrolysis is used to obtain such number for a range of processes. • The method is useful to determine if the effect from the operation of a process will lead to a net absorption of emission or net accumulation of emission in the environment.
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Highlights: • The present study highlights the association of MMR pathway with arsenic exposure. • Evaluation of the methylation status of key MMR genes. • Epigenetic repression of MLH1 and MSH2 due to promoter hypermethylation. • Significant down regulation of H3K36me3-the mismatch recognition moiety. • Impaired MMR pathway might increase susceptibility towards DNA damage and cancer. Arsenic exposure and its adverse health outcome, including the association with cancer risk are well established from several studies across the globe. The present study aims to analyze the epigenetic regulation of key mismatch repair (MMR) genes in the arsenic-exposed population.
Highlights: • Health benefits from a climate-financed cookstove intervention were limited. • Blood pressure changes were not significant in homes using intervention stoves. • Eye-irritation generally improved, suggesting unmeasured exposures or reporting bias. • Stove adoption and use behavior, in addition to stove technology, can complicate attainment of health benefits. Air pollution from cooking with solid fuels is a potentially modifiable risk factor for increased blood pressure and may lead to eye irritation.